>Do you like it being in the Japanese writing system or would you prefer phoenetical English? Wasn't sure which to do on that one.

Please do NOT use romaji. I honestly hate it when language-learning apps try to force romaji on me; it's not useful for learning the language. The written language in Japan is Japanese (hiragana/katakana/kanji), not romaji, so I just find it a distraction. Part of learning the language is learning to read it, not just to talk in it, and being forced to read it in its native script is far more useful than latin transliteration. That said, having furigana for unfamiliar kanji is really helpful too.